The invention relates to a press for the production and forming of workpieces acquiring their final form in a plurality of steps, with a transfer device for the stepwise displacement of the workpieces to individual forming stations of the press, this transfer device having at least one or two gripper rails which are movable back and forth in the advancing direction for the advance and return movement and possess gripper parts or gripper regions for grasping the workpieces, and which can be adjusted for grasping the workpieces and for moving in the advancing direction and subsequently into the initial position again, the transfer device having at least one gripper rail coupling with a coupling piece and with a coupling counterpiece fixedly connected to the gripper rail and designed to fit with the coupling piece, the coupling piece being separable from the coupling counterpiece and connectable to this for the tool change, and the coupling piece having a locking mechanism.
For the tool change on presses, particularly on transfer presses, it is known to release the gripper rail completely or at least in the region of the workpiece holders located on them, so that either a gripper rail piece, together with its drive, or the drive, without gripper rail, can be moved away from this and the gripper rail can be uncoupled and then exchanged.
An arrangement of this type is known from DE 42 34 997 A1, the mutual coupling of a piece of a gripper rail with a remaining piece taking place via a pivotable hook which has to be brought into the position of use, in the region of a bolt to be grasped, by means of a piston drive. In this arrangement, therefore, special controls and drives for actuating this coupling, for example an electric drive or a hydraulic drive, with a corresponding dead weight are required. There is also the need for hydraulic lines and/or cables for electrical actuations, which have to be moved along during each operating stroke of the gripper rails.